(57) ABSTRACT A method and apparatus for initiating a ran accelera tion of a projectile that
is at rest. A projectile (34) is positioned in a starting chamber (14) of a launch tube (12) …

A method for accelerating projectiles comprises introducing the projectile into an accelerator
barrel, feeding a combustible gas mixture into said barrel and igniting said mixture to …

A Hugoniot analysis of the quasi-one-dimensional ram accelerator propulsive modes is
presented which relates the thermodynamic properties of the stationary propellant gas to the …

One or more ram accelerator devices may be used to form one or more holes in geologic or
other material. These holes may be used for drilling, tunnel boring, excavation, and so forth …

In accordance with one aspect of the invention, a housing of a cartridge carrying a projectile
includes a sealed con tainer means including: a mixture of an oxidizer gas and helium gas …

(57) ABSTRACT A drill string comprises a mechanical drill bit and a ram accelerator with a
launch tube proximate to the mechanical drill bit. A projectile accelerated by the ram …

A ram accelerator device may utilize rails arranged within a guide tube that may be
emplaced downhole. The rails may serve to direct a hypervelocity projectile along the length …

(57) ABSTRACT A hole in geologic material, such as a wellbore, may be extended by
impacting the working face of the hole with high velocity projectiles. A tube may be placed …

A baffled ram accelerator system includes a ram accelerator tube with an inner surface and
an outer surface and a plurality of baffles disposed on the inner surface. The plurality of …

A wellbore or other type of hole in a geologic formation or other material, such as concrete or
other manmade structures, may be formed by accelerating perforating charges containing …